METHOD AND DEVICE FOR THERMOPLASTIC TUBULAR ARTICLE

摘要

PURPOSE: To provide a method and an apparatus for manufacturing a thermoplastic tubular article in mass production repeatedly controllable for the article by accelerating a natural orientation degree of a material faster than prior art of the article having high quality and good furniture. CONSTITUTION: In a special apparatus having a heating furnace including a plurality of nozzles differentially clogged, a simply continued temperature gradient is generated in an overall length of a preform. Elongation and radial expansion are started with a highest temperature end of the preform as a single starting site of the elongating and radial expansions in the axial preform, and the expansions are sequentially propagated along the preform to manufacture the article.